At Los Alamos National Laboratory, site of one of the world's most powerful scientific supercomputing facilities, a prototype network for an environment that links supercomputers and workstations is being developed. Driven by a need to provide graphics data at movie rates across a network from a supercomputer to a scientific workstation, the network is called the Multiple Crossbar Network (MCN). It is intended to be a coarsely-grained, loosely-coupled, general-purpose multicomputer framework that will vastly increase the speed at which supercomputers communicate with each other in large networks. The components of the network are described, as well as work done in collaboration with vendors who are interested in providing commercial products.